This invention relates to multifunction display arrangements for motor vehicles which include an electronic display unit having a picture screen to display information in the form of signs and symbols and at least one control member within the driver""s field of view in a part of the interior trim of the vehicle.
Increased traffic density and the desire of vehicle users for greater comfort have led to numerous electronic accessories in motor vehicles, such as guidance, warning, audio systems and mobile radios which provide large quantities of information and messages to be supplied to the operator. For presentation of such information, electronic display units, especially in the form of monitors or picture screens, which are increasingly coming into use, have the advantage that different data sets can be presented in time sequence at the same location. The reception of such a large quantity of information is necessary for the driver""s operation of the vehicle but causes a diversion of the driver""s attention from the road while reading the screen. For this reason, the duration of any such diversions must be kept as short as possible.
Various lighting conditions, incident light on the display screen and light or images reflected from the display screen may interfere seriously with reading of the displayed information. This results in a diversion of the vehicle driver""s attention for time durations that are often unwarranted in terms of safety.
To reduce light reflection from picture screens or monitors, for example, U.S. Pat. No. 5,288,558 and German Offenlegungsschrifts Nos. 41 00 831 and 41 17 257 disclose the application of antireflection coatings either directly to the surface of a display screen or to a sheet of glass in front of it.
To provide a display in a motor vehicle, U.S. Pat. No. 4,521,078 further discloses arranging the display surface of the display screen at an angle between the display surface and the direction of the viewer""s gaze which is different from 90xc2x0 to prevent specular and other reflections, and presenting characters on the inclined display surface which are distorted in such a way that they are viewed without distortion by the user.
Further, to diminish specular reflection in the display surface of a display unit in a motor vehicle, German Offenlegungsschrift No. 44 25 204 discloses a covering glass for a display screen which is oriented so that, from a driver""s average viewpoint, a portion of the instrument panel located in front of the display unit is reflected by the glass.
Because vehicle users have different stature and use different seat adjustments, however, such solutions do not always provide the desired result with every driver.
Accordingly, it is an object of the present invention to provide a multifunction display arrangement for a motor vehicle which overcomes disadvantages of the prior art.
Another object of the invention is to provide a multifunction display arrangement which, considering a vehicle user""s individual ergonomy and the lighting conditions under which the vehicle is operated in each instance, is easily readable because the effects of light shining into the vehicle and/or specular and other reflections from light-colored interior surfaces can be avoided to a large extent or even eliminated completely.
These and other objects of the invention are attained by providing a multifunction display arrangement having a display screen which is supported for pivotal motion on at least two axes.
According to the invention, at least the electronic display unit of the multifunction display arrangement may be mounted in an aperture of the interior vehicle trim, pivotably on at least two axes, preferably a vertical and a horizontal axis, to improve readability.
This has the advantage that, beside permitting an optimal orientation of the display screen in relation to directly incident light, the display unit may be adjusted with respect to reflected light colored areas or surfaces in the motor vehicle to provide a viewing or reading direction which is convenient to the user.
In accordance with one embodiment of the invention, the electronic display screen is part of a structural unit which also contains a control member or members, in which case the entire unit may advantageously be pivotable on the two axes.
Preferably for design reasons the angle through which the electronic display unit is pivotable in the aperture of the interior trim is no more than about 10-20xc2x0 on each axis.
The pivotal suspension of the electronic display screen or unit may be achieved in many different ways. Thus, in one embodiment, the display screen or unit is pivotable about a mounting constructed, for example, in the manner of a ball-and-socket joint. In this case, a socket member is provided in which a ball member, having the configuration of a partial or complete sphere, is rotatably held so that, upon pivoting of the display screen or unit about the joint, individual points of the picture screen surface follow a spherical motion path having a center of curvature which is located more or less at the center of symmetry of a picture screen surface of rectangular, oval or circular shape. For this purpose, according to another aspect of the invention, the center of rotation for the mount consisting of a socket element and a ball element is in the region of the surface of the multifunction display screen. For a display screen or unit mounted in a housing so that the picture screen surface is substantially flush with the front of the housing, the center of rotation is thus moved into the region of the screen. The center of rotation can be positioned to the front or rear of the screen, depending on the application, to the extent that the mobility of the display screen or unit as a whole is not unduly impaired. In the ideal case, however, the center of rotation is located exactly at the picture screen surface. The socket element and the ball element may be associated either with the movable display screen or unit or, at least indirectly, with the interior trim.
According to another embodiment, the display screen or display unit of the multifunction display arrangement is pivotable about a position which is essentially flush with the front of the housing in a mounting constructed, for example, in the manner of a telescoping ball-and-socket joint. For example, at least three socket elements are provided, in which ball elements in the form of partial or complete spheres at the ends of movable piston rods are rotatably held and are also displaceable lengthwise perpendicular to the normal position of the display screen so that, by appropriate pressure on the display screen or unit, the position can be adjusted to the direction of view of a user. Because the screen or unit is supported at several positions, individual adjustability to the needs of the user and to prevailing visibility and lighting conditions is possible.
It will be understood that the components of the ball-and-socket mountings may be reversed if desired, that is, the end portions of the piston rods may be in the form of socket elements, and the corresponding ball elements may be affixed to the rear of the display screen or unit. Reversing the components of the ball-and-socket mounting in this manner will not limit the mobility of the display screen or unit.
In an advantageous modification of this embodiment, coupling arrangements are provided to connect bearing mounts. Coupling of the bearing mounts may be accomplished by various mechanisms, for example mechanical linkages such as cables, hydraulic lines, electrical servo motors and the like. Because of the linkages of the bearing mounts, at least when coordinated in pairs, the axis of rotation of the display screen or unit is located at the midpoint of a line connecting the coupled bearing mounts, in other words a line parallel to the visible surface of the display screen or unit. An advantage of coupling the bearing mounts is that only pressure need be applied to adjust the display screen or unit. The distance over which piston rods acted upon by the applied pressure are moved into the housing is compensated by motion of the coupled bearings in the opposite direction. Thus an over-all motion of the display screen or unit to a position into the interior of the housing is prevented. Furthermore, no handles or gripping devices need be attached to the display screen or unit to effect a motion of a portion of the display screen or unit toward the user.
As one example, the coupling between bearing mounts may be effected by Bowden cables or the like. The use of commercially avialable Bowden cables or the like provides an economical, well-tried, dependable and easily replaced mechanism. Because of the built-in flexibility of these devices, their placement can be adapted to the requirements of the housing interior.
Further, by connecting the bearing mounts through fluid lines, hydraulic coupling can be effected and the hydraulic channels can be integrated to special advantage into the housing walls so that they require no space in the interior of the housing and the walls are not burdened by connections or holders. Also, the use of hydraulic couplings provides the possibility of intercoupling all the bearing locations and thus generating a center of rotation of the display screen or unit in the center of the area bounded by the end points of the bearing mounts.
It is also of advantage that, by suitable choice of viscosity of the hydraulic coupling, adjustable damping can be achieved. Thus, the display unit can be arranged so that it can only be pivoted slowly, avoiding any unintentional shifting of the display unit beyond a desired position. Furthermore, the damping effect of the hydraulic fluid prevents automatic restoration of the display unit to its normal position, so that a selected setting is maintained.
Pivoting of the display screen or unit by way of electrical signal detectors, signal emitters and servo elements advantageously assures that there need be no restriction as to placement of the conductors inside the housing. The conductors may either be integrated in the housing wall or laid along the wall. The use of servo elements permits a spatial separation of a control element and the display screen or unit, much like that of electrically operable window drives and outside mirrors. The control element may, for example, be mounted in the vicinity of the vehicle steering wheel so that a driver need not move a hand to the display unit while driving.
In another advantageous embodiment a multi-function display arrangement has a housing frame mounted in the interior vehicle trim and arranged to accommodate the movable mounting of the display unit. Such a multifunction display arrangement may be mounted as a complete module, for example, into an instrument panel or a central console. Alternatively, however, it is possible to configure the trim part as a housing for the display unit.
Because of the small structural depth of the display unit mount and its good angular adjustability, application of the invention to other information media is possible. Installation for example of one or more display screens or units in the backrest or headrest for the front seats to exhibit television programs or as a computer picture screen may be advantageously effected.